Ireland, a famously conservative country with a government dominated by the center-right, has taken a step toward legalizing same-sex marriage, following several other Catholic nations into what some say is belated equality – and others claim is murky legal and moral territory.

Ireland's Constitutional Convention, a body set up by the government to propose wide-ranging changes to Ireland's Constitution, voted Sunday, with 79 percent in favor of extending marriage rights to same sex couples.

Ireland's minister for justice and equality, Alan Shatter, issued a statement welcoming the vote and the "support expressed for the reform and modernization of our laws in relation to the parentage, guardianship, and upbringing of children."

The Constitutional Convention does not have the weight of law, but many feel it gives moral weight to the issue, effectively forcing the government to hold a referendum.

Any movement will not be swift: "I can't see a referendum coming for at least two years," says attorney Simon McGarr, citing the need for the executive to discuss the issue and then pass it to parliament before it is put to the people.

On the other hand, homosexuality remained officially illegal in Ireland until 1993. Conservative commentators point to the speed with which same-sex marriage has become an issue with some skepticism.

David Quinn of the Iona Institute, a multidenominational religious think tank, says the Constitutional Convention was only ever going to embrace same sex marriage.

"The outcome was 100 percent predictable," he says. "The public is being very heavily conditioned to be in favor of this, and the argument [being used] is highly emotive: we love each other, why can't we get married?' "

Mr. Quinn locates the rapidity of the shift in a consensus among the political elite seeking to distance itself from Ireland's often dark Catholic history.

"Two types of country are moving to embrace gay marriage: the Scandinavian [social democracies] and ones trying to escape a Catholic past that was authoritarian: Uruguay, Argentina, Spain, and [authoritarian to a lesser extent] Ireland," he says.

The central issue for opponents is not so much the marriages themselves, but the concept of family – with children at the center of the battleground.

"Attached to genderless marriage is genderless parenting and the severing of the natural, biological tie. It's an explicit denial of this," Quinn says.

Campaigners see things differently.

Moninne Griffith of Marriage Equality says civil partnerships for gay couples, which began in Ireland in 2011, were a move forward but are not true equality.

"People in Ireland know what separate but equal means," she says, referring to anti-Catholic discrimination prior to Irish independence and in the Northern Ireland of old.

"It's 10 years since [the first same sex marriage case] in the High Court. Even before then the Equality Agency issued a report on equal recognition of same sex relationships."

Ms. Griffith says there is overwhelming public support for the extension of marriage rights, though it is not high on many people's list of priorities.

Desire for a life-marking milestone

Ross Golden-Bannon, a restaurant critic, says he has no immediate plans to get married, but welcomes the Constitutional Convention's decision as an indication of a sea change in public opinion.

"Personally, I'm not in a relationship at the minute, but the big thing for me is, as a gay teenager, I didn't have the same life-marking milestones to look forward to as everyone else. That's quite psychologically damaging," he says.

The issue isn't quite as simple as a left-right divide, though it is fair to say that most opponents tilt conservative, while most supporters tilt liberal. Political support is near-universal, though.

The majority party in government, conservative Fine Gael, has no stated position, but senior party figures are known to be in favor. Its coalition partner, Labor, is also in favor, as is opposition party Sinn Féin. The other main opposition party, Fianna Fáil, supports a referendum.

Gay rights, yes, but marriage?

Maria, a graduate student who describes herself as left-wing and did not want to share her last name for fear of criticism, is concerned at the speed at which same-sex marriage has entered the mainstream.

"I think people are afraid to question if for fear of being labeled a bigot," she says.

She says gay couples should have rights, but that marriage is unique to men and women.

"I feel gay people have been persecuted and continue to suffer in a culture that is hetero-normative, but, for a start, I feel this debate has jumped from civil partnership to marriage. Marriage is a social institution for bringing together a man and a woman to found a family," she says.

She urges caution, saying unintended consequences are a real concern.

"[With same-sex marriage] society will have to look very seriously at issues like sperm donation and surrogacy. We could have a situation where [only] gay married men can't have a biological link [to their children] if surrogacy is disallowed," she says.

Mr. Golden-Bannon says the point is that gay couples are now accepted as normal, and the apparent speed of the move toward gay marriage is actually a result of people's lived experiences since 2010: More than 1,000 civil partnerships have been conducted in that time.

"The civil partnership legislation changed people's minds. Most people who went to ceremonies were ordinary people who have had no connection with the gay community – an auntie from Kerry, Jimmy from Donegal," he says. "They saw it wasn't Sodom and Gomorra. It became normal, and every local newspaper covered them."